It had U.S. labels, which suggests that it came from the States. Regarding the one that I didn't know where it came from, I'd probably be inclined, at least in that case, to go for one of the ones that I knew where they came from, rather than the one that I didn't. If none of them had any source designation on them at all, as a consumer I'd be very confused if I was concerned about the country of origin.
Sometimes these things are not necessarily top of mind. As Mr. Kyte suggested, price usually is the first consideration. Country of origin or “product of” or any of those terms are more likely to come to mind, depending on what external factors are at play at the present time--whether there have been media reports of certain incidents, different types of things, external forces that cause the consumer to think in those terms.
I too notice, as I go through the supermarket, that I'm standing there reading labels, while many people who are under much more time pressure than I am come by and just grab it off the shelf, sometimes looking at the lowest price.
If we have labelling, then I want it to be accurate. If we don't know, then we are probably better off not having anything and then leaving it up to the consumer to decide: do I want to buy that product that I don't know anything about, or find one that I do know something about?